1. Field of the Invention
The present invention relates to a method of manufacturing an amorphous magnetic alloy ribbon for magnetostriction delay lines and a use thereof for magnetostriction delay lines.
2. Brief Description of the Prior Art
There is known a magnetostriction delay line made from a magnetostrictive material, said line being capable of transmitting signals at the speed of sound by utilizing vibration resulting from magnetostriction. The magnetostriction delay line requires uniform performance. The presence of locally deviating performance, particularly with respect to the speed of sound, through the magnetostriction delay line may cause a deviation in a linear performance with respect to a delay time.
A coordinate digitizer requires a number of magnetostriction delay lines which are uniform in magnetic and mechanical characteristics. Such coordinate digitizer has a structure in which one hundred 120 cm long magnetostriction delay lines are disposed in intersecting lines with another one hundred 120 cm long magnetostriction delay lines under an application of tension. The coordinate digitizer is designed such that a pulse signal applied at one end of the magnetostriction delay line is detected by a pick-up coil mounted at an appropriate point in a plane in which the magnetostriction delay lines are disposed. A coordinate of the points where the pulse signal is detected is determined by measuring a time duration lapsed by the detection of the pulse signal in the lengthwise direction and a time duration lapsed by the detection thereof in the widthwise direction. In order to determine an accurate coordinate, it is thus required that the speed of sound is transmitted uniformly over a whole length, for example longer than several hundreds meters, of a magnetostriction delay line or a distribution in the speed of vibration propagation resulting from magnetostriction is uniform as much as possible.
An amorphous alloy metal ribbon having a positive magnetostriction constant as magnetic material is used in the prior art to form magnetostriction delay lines. The amorphous alloy metal ribbon is usually prepared by means of centrifugal quenching, single roll quenching or double roll quenching techniques. The ribbon thus prepared gives a wavy appearance, and a deviation of a distribution in internal stresses is caused during manufacture. These result in a deviation of a distribution in the sound speeds through a magnetostriction delay line thus prepared.